Tetrabutylammonium bromide (TBAB) can be synthesized via the reaction of tetrabutylammonium hydroxide with hydrobromic acid. The reaction is usually performed in an appropriate solvent such as water or an organic solvent. Another alternate route is the reaction of tetrabutylammonium chloride with silver bromide, wherein the chloride ion gets substituted with bromide ion. To achieve TBAB with high purity and good yield, careful control of the temperature, concentration, and reaction time is needed.